FinFET (fin field effect transistor) devices have become very popular in semiconductor device manufacturing because of the increased integration levels they provide. FinFET devices utilize fin-like structures formed over the surface of a substrate and provide increased surface area relative to planar semiconductor devices. Fins are generally formed of semiconductor material such as silicon and are narrow thin-like structures formed over the surface of a substrate. FinFET devices include field effect transistors formed on the fins. The added surface area provided by the fin is used as the channel and source/drain regions of the FinFET devices. Other active devices also utilize the additional area afforded by the fins. A greater number of FinFET devices than planar transistors, can be produced on a given footprint area of a substrate. Further, for a given footprint area on a substrate, a FinFET transistor can be formed to include larger source/drain areas, larger channel areas and larger gate areas than a comparable planar transistor formed on the substrate surface, thereby increasing the device speed for FinFETs. Fins are generally formed parallel to one another over a substrate for ease of manufacturing and due to limitations and photolithography and etching processes.
In the manufacture of FinFET devices, the fins are generally initially formed throughout the die including in active areas where they will be utilized and also in other areas where they are not needed. The fins are subsequently removed from areas where they are not needed. The removal of fins from some areas but not others is susceptible to patterning problems that are associated with non-uniformities and irregularities in the masks used to remove the fins from the undesired areas.